Sampling apparatus



Oct. 6, 1953 J. vxsMAN SAMPLING APPARATUS 2 Sheets-Sheet l Filed Ol.. 5, 1950 FIGJ FIGJG Oct. 6, 1953 2,654,249`

J. VISMAN SAMPLING APPARATUS Filed Oct. 3, 1950 2 Sheets-Sheet 2 lnuenfor J'dn Vl's man I @M/MM Patented Oct. 6, 1953 SAMPLING APPARATUS Jan Visman, Brunssum, Netherlands, assignor to De Directie van de Staatsmijnen in Limburg,

Heerlen, Netherlands Application October 3, 1950, Serial No. 188,159 In the Netherlands October 12, 1949 (Cl. 'i3-424) 7 Claims.

The present invention relates to an apparatus for sampling a small-quantity of material which is representative of the average of some large amount, and more particularly to apparatus for mechanically obtaining sample quantities of heterogeneous granular material, such as coal, ores and the like, from abulk of such material as it is moved or transported past a sampling station. f f

Heterogeneous granular materials are composed of small lumps or particles dilering in diameter and composition, and examples of such materials are coal with a low ash content, or a high grade ore with valueless gangue. In order to examine the properties of heterogeneous granular materials to determine their composition, it is a common practice to take samples therefrom and to analyze the samples.

Sampling usually consists of taking portions or cuts periodically from a stream of material as it moves or is being transported past a sampling station. A number of these samples obtained from the different parts of the bulk material are combined to form a gross sample. Contents of the gross sample are thoroughly mixed and usually7 after crushing, a sample is taken therefrom of a size customary for analyzing.

The diierent sizes of granules of the heterogeneous material to be .sampled tend to segregate when the material is being transported on a beh-type conveyor or when it is dropped from the delivery end of such conveyor or when dropping from an inclined conveying trough or pipe. The larger lumps or particles will move relative to the smaller ones.

Presumably, on account of this segregation, well known automatic samplers such as the guillotine coal sampler (Vide Colliery Engineering, volume 22, page 117 (1945)) and Grppel Probenehmer (vide Glckauf, 1935, page 705) have been designed to cut portions or samples periodically from a passing stream of material by intermittent trans-verse movements across the stream. The width of these cuts depends on the Width of the sample cutter, which cuts across the entire Width of the stream of material to be sampled. y

Thus the size of every sample will be comparatively large if the stream of material is wide, as is usually the case With products transported in bulk. The gross sample, consisting of a combined number of samples taken periodically, consequently will be undesirably large and therefore diiiiculties are encountered and errors occur in reducing such al large quantity into a fair '2 Y c sample of the size customarily used for analysis. The greater accuracy which might be expected to result from a large total sample is not attained. In the past, it has been a practice to take samples of comparatively large size and in the case of coal, the incremental weights of the samples have been specied to range from 1/2 to 2 kg. This range, which has been accepted in the past, is obtained from the ratio between the weight of the separate sample increments and the particle size of the particular material to be sampled. The weightof the sample (expressed in lbs), should be at least equal'to two or three times the diameter (measured in inches) of the coarsest particles as suggested in the British Standard Institution No. 735-1944, page l9, table la, and the A. S. T.M. Standards on Coal and Coke, September 1948, page 4, table II. Contrary to this established concept, I have shown and published in the Trans World Power Conference 1947, volume II, pages 430-441 that a higher sampling accuracy can be obtained by taking a larger number of individual samples of smaller size. In addition, I have discovered that it is unnecessary for the weight of a sample to be more than a few times the individual Weight of the coarsest particles in the bulk material. I have also found that it is unnecessary for a sample to comprise a complete cut across the stream of material in that it may be a small fraction of such a cut provided a suiciently large number of such small samples are collected. By taking a large number of small samples, a sample can be obtained that is thoroughly representative ofr the average of the entire stream of material.

Therefore, an object of the invention is to provide a sampling apparatus which will take up the particles constituting the sample from substantially the interior of the stream of material. A more accurate representation is obtained by taking a sample from the interior of the stream since the chances of segregation of the heterogeneous granular material are relatively great at the surface of the stream.

A further object of the invention is to provide a simple, compact', practical and reliable sampling apparatus by means of which a sample of relatively small size may be taken up at regular intervals from the stream of materialas it moves or is transported past the sampling apparatus.

A still further object of the invention is to provide an apparatus for taking a sample where the minimum weight of the sample will only be a few times the individual weight of thercoarsest particles present in the heterogeneous material.

These and other objects of the invention will appear more clearly from the speciiication, claims, and accompanying drawings in which:

Figure 1 is a front elevation of the sampling apparatus mounted over a belt conveyor.

Figure la is a sectional View on the line I-I of Figurel M' Figurel lb a sectional View on the-line II-II of Figure 1.

Figure 2a is an enlarged longitudinal cross-` sectional view of the sampler tube.

Figure 2b is an enlarged longitudinal crosssectional View of a modiediformgofrthesample tube.

Figure 3a is a plan view from beneath the sample tube of Figure 2a..

Figure 3b is a plan View fromkbeneathrthe modiiied sample tube of Figure 2b.V4 m

Referring to the drawings, wherein like-character or reference numerals represent like or similar. parts..-zthe sampling apparatus. comprises afzhellgw. discharge tubel .havinga detachable tapered., sampleilllecting .tube or .nozzle.3,..con nected'gin-,axialLalignment therewith.v One or moregdischarge tubes. Land-.the samplecollecting tubes 3 arefmounted-.ior.rotation onY a ,horizontalshafts I locatedltransyersely, over,` a belt..conveyor 91er thelike. Any suitablemeans may be usedto attach .thefrdisharge ,tube 2 A to the K rotatable horizontalrshaft Ii and3as, bestshown in Fig.` 1a and; .1b.- sthe. tube. Lmay, be l.Welded to a .rectangularishankportlon -of.;the -s hait I. As netedin Figure l, .the planeof .rotationofthe discharge and samplecolleeting .tubesis on anincline from the. ,vertical sa` thatgfthesample collecting. tube 3 canalis-swung through. the .materialeto ,besampledinan. arcuate-path, opposite the;direc tion uof .iilovemenig` otjthe stream of, material to be. sampled.

Horizontal shaft. luis-,supported over the. belt conveyors 9.A bynmeans, oi vthe .bearing I d and` a motor. which is also used'todrive, it; -A- Casing I Il, Which.ho1.1ses;themotor,. alsohouses a time relay and a circuit-,breaker 4,.so:.that the shaft Land the :sample collectingand dischargetubesmaybe intermittentlyfrotated atpredetermined intervals;v It is x*obvious .that :the .intervals for .rotating Vthe samplecollecting.tube. may. beyaried, depending on Y the material to `4be sampled. AsA lanrexarnple, the `apparatus can .operatetoltake' :15, samples ,per minute. :With a-stram otmaterial. moving at a speed-of 2. mJsec. and .conveying 200 .ton/h.,= the sampleeollecting-tube may` be... operated. to take samples. vaveraging llto 2.os.,..with a. maximum particle-size-being 8mm.

f-Referringspecically toFigures 2a, and.3a,..the samplecollecting-tube 3 is `connecte`d..to.the discharge tube 2`bymeans of a flangeflfand'a screw bolt i1. Sample vcollecting .tube 3. whicliltapers from a flange :I 6.4 to an .end closureavall I 3, .has a nose-like projection I'2 adjacent. to. themend" closure f wall. fl3. Noseflikee projection .42. .is formed bybending the wallof the sample collecting tube 3 outwardlyso..asto..produce a;.local radial enlargement ,at -the end'` of .theL tube. An orifice l I is,I proizided-V in: the. end: closure .wallgl 3 for `receiving themateriaLto-be Ysampled.andJlies in an: plane substantially tangentialto. the .locus of.k the center fofzfthe Qrilce. :viThe .purpose of;.the noseielike:proiectionel-is totshield .theloriiice IL when thesample collecting .tube 3initiallyenters the vstream ci. material, whereas the. ,end closure Wall; I3 .serves to..arrest -the particles from .entering-.the .orifice i I I.. duringztthe .final movement.; of

the tube. outfof. .the streaxrnas .it willstop .the im;

mediate underlying material when it is sufficient- 1y inclined. to the vertical. Thus, material Will only enter the orice during the medial portion of the arcuate movement of the sample collecting tube 3 through the stream. This occurs when the leading edge of the nose-like projection is at fa liigliel level than the' '"'tiailirigjedge' of the brie and' the incline"from the'ver'tical of the end wall I 3 is not suiiicient to arrest the particles lf-` material in the stream.

-,Theleading edge of portion p of the orice Il,

Whihueresponds to the tip of the nose-like projectionand thev trailing portion q of the orific I Larelsharp'ene'd to promote a cutting action through 'the material when the sampling appara- ,.vtuskis. operation. Since it is only necessary to gtakeifanliriiirfidual sample which is a few times the windiyidual Weight of the coarsest particle present in the material, the size of the oriiice need only be a little greater than the coarsest particle of material' to. be sampled. lThe, shenrpcned portionspiandq of the samplereceiying orifice ,Willcut through any particles -Whichcohere. to one n another.

,Mountedvon theshaft I adjacentwthe casing I Il; is a leyer arm4 3 .which 'contactsa switch I5 on the. automatic timing.deviceIt` when lthe sample collecting tuber 3 is `in thejnverted position. This will stop the motor, thus stopping rotation of the ,shaftA Lia-nd, the samplecollectingv tube 3. The sample. colleetedln the. .tube 3. Wllldeeharge through thefreliecharee. tube. 2, `iam a pipe ii. .which willie .turn deliver .the samelete aeuieble. .receiver ...Since material may.. elingwthn .the ,Sample collecting tube.. when. .it is. inverted.. e ,striker `or keeelier eieprovided teepnteet .aeeinetthe eide of the discharge ,tube 2 .to release clinging materiel through thefreeendthereef- 4-l'he kneeker E ,ismountedgon an arm 5a.v connected l,to asleeve 5b. Ae clearly zehowninrieure le. EYSleeve. 5b. ie freely..rotatable.relativetel the-.Shaft l,V and. .when the.. Semeleeolleetne tube-i ereieed upwardly. it. .Wi1l c,arry, withjt ,the knoclzer 5 untilthe kneeker; .hee.paeeecl..deed centerei the shaft. Kneeker; 5.. Will, then .reteteldwnwardly under gravity andstrke the Side Oflhe dlSQherge tube l-flling .2413.- Clnglng .material rieures .2b and. bteielelese amediedierm. 0f eemeleleelleetlne,tube .This .Sample eelleeiine tubeie essentially .theseme .eetle. ene disclosed in rieure 'Zweite the.. exeeptien, thee the. .end closure plate 13e .has.eaupwerdlyinellned member ,l 3b. ,-{Ijhe v inclinedend member i312 is also provided with a sharpened portion q. Orifice II,

' @this instance will have a traiungee'gewhich eer'reereeile, .with f the. 0fflllllereellfef ille planeeei-.ihe enel Wellliaa .containing theerillee andtheinclllld endwall I3b. In sampling Wet,

Y neeeal.. a .Sample eelleetine, tube provided. with. theiangled, end. .closureA .wall .13b is. necessaryso thatduringthennal movement ofrotaten ofthe sample. .collecting A .tube ,through thematerial, a Smell @meent .0f7 the-,materiel .maree-ke ,Guille angled vend closure .wall .and Close Aolf.-,.'l1e.ellfiee to.. prevent material ...from. iurthel: entering the Orifice,

.1hao11eration-otthedei/'learner.beeummarlzed asiollowstample collecting tube Si. isretatecin anarcuatepathena pla-.ne .inclined tothevertllike projection I2 will close off and shield the orice during the initial part of the arcuate movement through the stream of material. Once the sample collecting tube has passed through the vertical plane mentioned above, the orice will then be opened to receive material from the center of the stream because, as previously stated, the nose-like projection will rise to a level higher than the trailing edge of the orice. The sample received in the sample collecting and discharge tube will be transferred through the open end of the discharge tube when the sample collecting tube 3 and discharge 2 are inverted. A knocker 5 which is freely rotatable on the shaft I is carried by the discharge tube 2 upwardly and past the dead center of shaft I. It will then fall by gravity and strike the side of the discharge tube 2, dislodging any material caught therein. The material picked up by the sample collecting tube 3 is transferred from the discharge tube 2 to a pipe 6 which delivers it to the sample receiver 'I.

The terminology used in this specication is for the purpose of description, and not for limitation, as the scope of the invention is dened in the appended claims.

I claim:

l. A sampling apparatus for obtaining a multiplicity of small samples from the interior of a moving stream of heterogeneous material comprising in combination a sample collecting tube with an end wall having an orice therein at one end thereof, means for rotating said sample collecting tube in an arcuate path through the stream of material, said tube having its wall adjacent the front of the orifice bulged out into a nose-like projection to prevent material entering said orifice when the sample collecting tube initially enters the stream of material.

2. A sampling apparatus for obtaining a multiplicity of small samples from the interior of a moving stream of heterogeneous material com-- prising in combination a sample collecting tube having side walls and an end Wall, there being an orice in said end wall for receiving the sample of material, a nose-like projection formed in the tapered side wall adjacent to said orice, means for rotating said sample collecting tube in an arcuate path into and out of the stream of material so said projection will shield said orice when the sample collecting tube initially enters the material, said means including a horizontal rotatable shaft, said tube being mounted on said shaft with the longitudinal axis of said tube inclined to the vertical.

3. A sampling apparatus of claim 2 wherein leading and trailing edges of said oriiice are sharpened so as to present a cutting surface.

4. A sampling apparatus for obtaining a multiplicity of small samples from the interior of a moving stream of heterogeneous material comprising in combination a rotatable horizontal shaft supported above and transverse to the stream of material, a discharge tube mounted on said shaft for rotation and having the longitudinal axis thereof inclined to the vertical, a sample collecting tube having an end wall at one end thereof detachably secured at its other end to one end of said discharge tube and in alignment therewith which will rotate in an arcuate path into and out of the stream of material, a nose-like projection formed in said sample collecting tube by bending the surface near said end wall outwardly so as to produce a local radial enlargement, and there being an orice in said end Wall adjacent to said nose-like projection for receiving the sample of material from the interior of the stream of material.

5. A sampling apparatus of claim 4 in which one edge of the orice as dened by the nose-like projection and an edge formed by the trailing portion of said orifice are sharpened to promote a cutting action through the material tube sampled.

6. A sampling apparatus of claim 4 wherein means are provided to dislodge material clinging to the sides of said discharge tube when in an inverted position, said means including a freely rotatable knocker member mounted on said horizontal shaft, said knocker member being rotated upwardly by rotation of the discharge tube and rotated downwardly by gravity.

'7. Apparatus of claim 4, wherein said end wall containing said orioe is provided with a trailing edge which is inclined to the plane of said orifice.

JAN VISMAN.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,964,270 Nidever et al June 26, 1934 2,301,815 Robison Nov. 10, 1942 2,327,123 Morse Aug. 17, 1943 2,336,539 Gilbert Dec. 14, 1943 2,495,944 Pletta et al Jan. 31, 1951 

